That 1.6 gallons left him holding a quart of milk, a winner at the Brickyard for the second time in four years.

“Still running,” the winner told his crew over the radio as he crossed the finish line, while wreckers were moving out to scoop up debris from an accident that sent Mike Conway into the wall and to the hospital with a broken left leg.

The victory made Franchitti’s boss, Chip Ganassi, the first owner to win Indy and NASCAR’s Daytona 500 in the same year.

“All he wants to do is win,” Franchitti said.

This win validated the Scottish driver’s return to the IndyCar circuit two years after celebrating his 2007 Indy victory by making an unsuccessful move with Ganassi to NASCAR.

It also made Franchitti and crew look like the master tacticians they were on this day — working the gas pedal perfectly to stretch their final fill-up for the last 37 laps and edge out 2005 champion Dan Wheldon of England.

“You have to be prepared for all eventualities there,” Ganassi said. “We had to play that game being the leader to keep those guys behind us, but also stay in front of them to make it to the finish.”

Franchitti was holding off Wheldon when Ryan Hunter-Reay ran out of gas and slowed suddenly with Conway coming up alongside him. Conway went airborne, flipped upside down and flew into the wall, nearly landing on top of Hunter-Reay. That brought out the caution flag for the final lap.

“That car should have come down on my head,” Hunter-Reay said. “I don’t know how it didn’t.”

And so, Franchitti’s second victory turned out to be the story instead of Helio Castroneves’ fourth. Spiderman’s quest to tie A.J. Foyt, Al Unser Sr., and Rick Mears for most wins ever at the Brickyard essentially ended with an uncharacteristic mistake — stalling out while leaving the pits on the 146th lap.

It left Castroneves in need of a yellow-flag miracle at the end that never came, and he finished ninth after one last pit stop on the 192nd lap.

“Unfortunately, silly mistakes put us in the back,” Castroneves said. “I’m very disappointed. I’m more disappointed with the mistake.”

Danica Patrick made no such mistakes. After being booed during qualifying for complaining about a balky car, she picked and poked her way from 23rd to sixth.

Patrick never found her comfort zone in the 88-degree weather — at one point saying she wished she could make up as much time on the track as in the pits — but she was patient and disciplined and now has five top-10 finishes in six years.

Marco Andretti was third, followed by England’s Alex Lloyd and Scott Dixon.

“I’m very happy with the result, and the reasons we got it were that our pit stops rocked and we had a perfect strategy,” Patrick said.

Not so for Tony Kanaan, who finished 11th after starting last in the 33-car field and moving as high as second, less than half a second behind. His bid to become the first driver in 94 years of Indys to go from worst to first ended when he had to go to the pits for a splash of fuel with four laps to go.

“I hope I made it exciting out there,” Kanaan said.

Franchitti said he didn’t forget about Kanaan, even after the Brazilian stopped for the quick fill-up.

“I was concerned about running out of fuel. I was concerned about Tony, that he pitted,” Franchitti said. “The guys were, like, ‘Just get to the finish. Just see if you’ll get to the finish.”

The crew started pressing Franchitti to conserve fuel with about 15 laps left. He did as he was told, and after leading 154 of the first 199 laps at speeds of up to 224.287 mph, he slowed steadily at the end — to 210 mph, then 209 and 206.

Wheldon, whose crew was also telling him to slow, started bearing down, positioning himself to make the last lap of the Indy 500 the first lap he had led all year on the circuit.

Could he have caught Franchitti?

“I don’t think he could have picked us off,” Ganassi said.

He never had to find out. That’s when the cars behind them went flying.

“Maybe if I was young, I would have totally ignored them, tried to run Dario down when I saw him slowing down,” Wheldon said. “Just one of those things.”

With the yellow flag out, Franchitti’s wife, actress Ashley Judd, put her hand over her head, hoping her man had enough fuel to make it. He did, and a bit later, he was wearing a milk mustache in Victory Lane.

“It’s much easier when you’re just running wide open,” Franchitti said. “But that’s part of it. Strategy is part of racing, whether it’s IndyCar racing, stock car racing, sports car racing, you have to find the best way to get to the finish line.”

Both times he’s crossed it first at Indy, he’s crossed it without really racing. In 2007, he won when the race was shortened to 166 laps because of rain. This time, the end came under slow, yellow-flag conditions that froze the order of finish.

Ganassi said the key was getting a four- or five-second cushion early so Franchitti could hold off Wheldon at the end when he was conserving fuel.

“The worst thing you can do, and we’ve done it, is come up second in this race or third and have fuel in your tank that you didn’t use,” Ganassi said.

How far would the remaining 1.6 gallons have gone?

“I have no idea,” Ganassi admitted.

Ganassi won his fourth Indy and has a slice of history — first owner to win at NASCAR’s and IndyCar’s biggest races in the same year.

“We go racing, and we like to win,” Franchitti said. “To be a part of a team like that just makes your job so easy as a driver.”

It didn’t hurt the Ganassi guys that Roger Penske’s team was enduring an unusually bewildering day, as The Captain went for a 16th Indy victory.

More than an hour before Castroneves stalled on Pit Road, teammate Will Power’s crew left part of the fuel rig in his tank — a costly mistake that forced Power to take a penalty run through the pits and dropped him out of the top five.

And moments after Castroneves’ error, his other teammate, Ryan Briscoe, careened into the wall and out of the race while Penske looked on — hand on hip, seemingly amazed at how his smooth-running machine fell so far, so fast.

“As a team, we made too many mistakes today,” Power said. “We had a bloody fast car. I think we could’ve hung with Dario, no problem. It’s the lesson of this place. You can’t make mistakes.”

Power’s problems were part of an overall sloppy day at “The Greatest Spectacle In Racing,” which endured nine caution periods, including one when Davey Hamilton, the oldest driver in the race, crashed before the drivers made it out of Turn 2 on the first lap.

Dixon, Franchitti’s teammate, lost his left front tire coming out of pit road. Raphael Matos, who got to second early in the race, dropped back when his right rear tire came off — then went out when he hit the wall on lap 72.

Power crept his way back into the top five briefly, but another pit-road mix-up cost him time. The 29-year-old Australian, first before the race in the IndyCar standings, finished eighth.

Andretti started 16th and actually led one lap thanks in part to his early use of the speed-boosting “push to pass” button that was making its Indy debut this year. But without as good a car as the leaders, he fell back.

Nobody ran a cleaner, more tactically superior race than Franchitti. He had the third-fastest car in qualifying, which also helped, as did a little bit of racin’ luck at the end — the kind that has come to him much more easily in the open-wheel world than during his half-year in NASCAR in 2008.

But Franchitti’s departure didn’t mean the end of Ganassi’s stay in NASCAR. The owner won the Daytona 500 with Jamie McMurray at the wheel in February.

Had Franchitti had that kind of stock car in 2008, he joked, he might not have been sitting where he was Sunday.

“It all worked out perfectly,” he said. “We went on a little holiday, came back and now, we’re having some fun.”